Shapeways Custom Lego Parts

[jantjeuh]

Let us know how the quality is!

[Jim]

Let us know how the quality is!

Sure, I'll do a mini review on all parts!

[TasV]

Nervous now LOL I use CNC routers all the time at work but this is the first time I've had something printed in 3D... I really hope it works. I have plans to design and print a whole robot shell if it works.

I'll get the review on the liftarms started by going through the file used to make them.

I used Google SketchUp 8 (Just downloaded SU Make and am using that now too) with plugins allowing me to export STL files directly from SketchUp. Each part is made up of two modular parts so that any length piece can be made. They look like this:

These two parts are made up of 8230 different faces which is mainly due to trying to get sufficiently high enough resolution in the circles/curves to prevent the facets from being visible in the final product. When combined into a liftarm each piece can therefore be made of up to 80,000ish different faces. I probably don't need to go to this resolution but I wanted the pieces to be as smooth as possible given that 'stepping' can be introduced as an artefact of the printing process. Printing is achieved by laying down layers of material that is sintered by a laser. Because it is printed in layers there may be visible edges between each one, where it changes size, that causes this stepping.

The dimensions were based on the image posted on page one of this thread. Each component was made at 100 times the actual size and then scaled down because SketchUp has a really annoying snapping function that can't be turned off (that I am aware of) that turns otherwise straight lines into bent lines in cases where curves intersect with the straight line. Scaling it up, and then scaling it down once finished avoids this.

Edited September 17, 2013 by TasV

[Mtx]

At work I just finished assembly of 3D-printer which should be capable of making fully production quality parts. I'm eager to see how well it will manage with bricks. For sure I know that printing method is diffirent than shapeways.

[TasV]

Mtx, if you would like me to send you the stl files (once the parts have been tested) just let me know.

[chorlton]

These two parts are made up of 8230 different faces which is mainly due to trying to get sufficiently high enough resolution in the circles/curves to prevent the facets from being visible in the final product. When combined into a liftarm each piece can therefore be made of up to 80,000ish different faces. I probably don't need to go to this resolution but I wanted the pieces to be as smooth as possible given that 'stepping' can be introduced as an artefact of the printing process. Printing is achieved by laying down layers of material that is sintered by a laser. Because it is printed in layers there may be visible edges between each one, where it changes size, that causes this stepping.

I can't recall all the maths, but if you know the "resolution" of your printing artifacts or layers , then you shouldn't need to go beyond twice that for your model. So if your layers were 0.5mm deep then you should get away with facets no bigger than 0.25mm.

[Mtx]

Thanks TasV, I keep that in mind!

I'm still missing material cartridges so I am not able of printing anything. I have couple files already for tests what I have done with our old 3d-printer. Only problem with those were that the look of the parts were awful. I had then only white abs and the printing quality was far from satisfying. But durability was good if the part was printed in correct way.

New machine should make totally smooth surface even in transparent colors.

[TasV]

Chorlton, that makes sense. I will check on this. I might be able to give my poor laptop a break instead of trying to render overly complex files.

[Burf2000]

See I have some very cool metal parts but generally I have never used them. I do however use Rotacaster Wheels and 3rd party sensors, the NXT2Wifi is a good one, Mindsensor and Dexter also make some cool ones.

The LEGO Wheelchair would not of worked without Rotacaster!

[Jim]

At work I just finished assembly of 3D-printer which should be capable of making fully production quality parts. I'm eager to see how well it will manage with bricks. For sure I know that printing method is diffirent than shapeways.

Looking forward to seeing some of your work!

See I have some very cool metal parts but generally I have never used them. I do however use Rotacaster Wheels and 3rd party sensors, the NXT2Wifi is a good one, Mindsensor and Dexter also make some cool ones.

The LEGO Wheelchair would not of worked without Rotacaster!

I was really hoping that TLG designed and included Rotacasters with the EV3 set. Much better than the metal caster ball, although that's not too bad for simple robots.

[TasV]

I've had a chance to play with the metal caster ball by retro-fitting it into the NXT 2.0 set and have found it really good so long as the robot track is flat. As soon as they start throwing obstacles at you that are 5mm high, or higher, it gets stuck because the socket housing sits down too far over the ball preventing it from being able to roll over it. It can be fixed by attaching suspension to it (not mounted vertically though... it needs to be able to swing up out of the way and snap back into place once over the obstacle) but that's not always possible in robots that have to comply with dimension restrictions such as the RoboCup Junior rules that state the robot can't be more than 18cm high or wide. I have two of the smaller Rotacaster Omniwheels and they are great, BUT, and this is a pretty large BUT for an anal retentive builder like me, it is an odd size that means I can't mount it evenly right in the middle, parallel to the central axis, of the robot without it sitting more to one side than the other. That really bugs me and is why I bought two of them so I can mount them on either side like a car instead of just one at the back. It's also not the same height as any of the standard lego tires which means you need to get creative in levelling the robot/vehicle out.

These are the reasons I start looking at making my own pieces. If one is going to design and make 3rd party pieces they should at least made along the same ratios as genuine Lego.

Edited September 18, 2013 by TasV

[Jim]

My order has been delivered!

I will try to write a mini review this week.

@TasV the liftarms seem to be quite usable

[TasV]

Awesome...I had a guy contact me today asking me to make the 1x16 liftarm available for sale... I told him they were currently being tested and I had no plans to offer them for sale until they were fully tested. I'm most interested, in no particular order, in the quality of the finish, their strength, how well pins fit, and how well they fit with other pieces.

How does the alumide one look??? On a related note... I use powdered aluminium at work at times and it is very dangerous stuff. If you have young kids I would not be letting them near the alumide pieces.

Edited September 30, 2013 by TasV

[Jim]

Okay no need to wait for a review.

Almost every piece I order has holes that are a little bit too small. Same goes for the liftarms. The pins with friction need to be forced a little bit and the frictionless pins act like friction pins in official liftarms. I have read this in reviews of other parts as well.

Strength, I don't know. They seem a bit weaker.

The size is okay. I have connected them to official liftarms and the holes align perfectly.

Overall usability is okay! May need to widen the holes a bit.

I do think (know for sure) that these parts will have more wear and tear when being used.

[TasV]

Any chance of a photo or two?

[Jim]

Any chance of a photo or two?

Sure, of course.

But I am not at home right now. Will make some pictures when I get home. Really need to get myself a new digicam, but I will try to find my old one. iPhone pictures are so so.

[TasV]

Cool... thanks Jim :)

[Burf2000]

Shows us the parts lol

[Jim]

Shows us the parts lol

Will do, will do

By the way; I am sending you the other parts this week, so I can include two of these.

[jantjeuh]

Print me some Power Puller tires

[Jim]

Print me some Power Puller tires

Here's an image of the Liftarms. You can clearly see the graininess.

Original Image

I really need to get myself a better camera. Sorry for the quality.

Original Image

[jantjeuh]

Oof. That looks really bad That and the bad fit with the axles/pins leading to a lot of wear makes me wait a bit for the technology to mature before using custom parts.

I assume that white gear is a clutch gear and has dog teeth on the other side? You can just destroy old-style differentials to create those you know

Edited September 30, 2013 by jantjeuh

[Rishab N]

I think I'll print myself a couple of black 19L flex axles

[Hrafn]

I think I'll print myself a couple of black 19L flex axles

Would it be possible to print a flexible axle that didn't have the stops on the ends? That is, a flexible axle that could actually transfer drive to gears and wheels? Or are all the material options too fragile?

[aol000xw]

For very low torque plastic could work but you need a somewhat rigid outer so the flex axle can rotate inside without deforming.